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<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>箭头函数参数和返回值</title>
</head>
<body>

  <script>
    //1.参数问题
    //1.1一个参数
    const sum = (num1, num2) => {
      return num1 + num2
    }

    //1.2放入一个参数
    const power = num => {
      return num *num
    }

    //2.函数中的代码量
    //2.1函数代码块中有多行代码
    const test = () => {
      //1.打印Hello World
      console.log('Hello World');

      //2.打印Vue.js
      console.log('Vue.js');
    }

    //2.1函数代码块中只有一行代码
    // const mul = (num1, num2) => {
    //   return num1 * num2
    // }
    const mul = (num1, num2) => num1 * num2
    console.log(mul(20, 30));

    const demo = () => console.log('Hello Demo')
    console.log(demo());
  </script>
</body>
</html>